It is best if all servers share a
common network switch. Having multiple network switches increases the
possibility of a network partition occurring. If multiple switches must be used,
redundant routing paths should be available, if possible. The weight of members
sharing a switch in a multi-switch configuration will determine which partition
survives if there is an inter-switch failure.

In terms of GemFire configuration,
consider the weighting of members. For example, you could assign important
processes a higher weight.